Conveyor sheet cargo container method

ABSTRACT

The method of unloading provides for unloading of a cargo container without having to tip the container up on its end to cause a gravity flow. The method provides for placing a liner on the floor of a cargo container with side walls, front wall, ceiling and back opening. Suspending a bulkhead at the rear opening of the container from an upper portion of the container so it does not depend upon the floor for support. Placing a cargo within the container on the liner. Removing a bottom portion of the bulkhead and attaching an end of the liner located at the back opening to an unloading apparatus which has been detachably connected to the rear of the container, and then pulling the liner out, and as the liner is pulled out, the cargo on the liner is unloaded from the container.

This application is a continuation of application Ser. No. 08/155,422,filed on Nov. 19, 1993, now abandoned, which in turn is a divisional ofapplication with Ser. No. 07/732,451, filed on Jul. 18, 1991, nowabandoned.

BACKGROUND OF THE INVENTION

This invention generally relates to cargo containers; and morespecifically, to cargo containers of the type from which bulk cargo isdischarged by pulling a bottom or floor liner out from the container.

Standardized containers or boxes have come into very extensive use forthe shipment of freight by land and sea, and the many advantages of suchintermodal containers have made it very desirable to adapt them for usewith as many types of cargo as possible. Accordingly, there have beenattempts, with varying degrees of success, to use such standardizedcontainers to carry bulk cargo such as dry bulk chemicals, powdered andpelletized resins, flour, coffee beans, and grains. In particular,considerable attention has been given over the last several years totransporting such cargo in bulk in standardized intermodal cargocontainers--that is, in containers in which the cargo is loaded directlyinto the intermodal containers, without first being loaded or packedinto smaller boxes or packages that are then loaded into the intermodalcontainers.

Commonly, when a cargo is transported in bulk in a large, intermodalcontainer, the cargo is discharged from the container by tilting thecontainer so that the cargo slides out the back of the container underthe force of gravity.. While this cargo discharging method has receivedsignificant commercial acceptance, it has a disadvantage in that itrequires an expensive apparatus to tilt the container.

With another method for discharging bulk cargo from a cargo container, apleated liner is first placed on the container floor when the containeris empty, and then the cargo is loaded into the container, over theliner. To discharge the cargo from the container, the liner is pulledout from the cargo container, pulling the product out from the containerwith the liner. This cargo discharging procedure has not receivedwidespread commercial use, however. A primary reason for the lack ofcommercial use is that, heretofore, the industry has not been able toprovide a discharging method of this general type that, on the one hand,effectively unloads the entire contents of the cargo container, and onthe other hand, is still comparatively simple and economicallyacceptable.

SUMMARY OF THE INVENTION

An object of this invention is to improve methods and apparatus fordischarging bulk cargos from cargo containers.

Another object of the present invention is to provide an economical andeffective method for discharging bulk cargo from a cargo container, ofthe type in which a bottom liner is pulled out from the cargo containerto pull the cargo out therefrom.

A further object of this invention is to provide an improved liner forlining the bottom of a bulk cargo container, and that facilitatescompletely unloading the cargo from the container when the liner ispulled out from the container.

A still another object of this invention is to provide a system forsecuring a bulkhead inside a bulk cargo container, that eliminates theneed to use the floor or a bottom portion of the cargo container tosupport the bulkhead.

An object of the present invention is to suspend a bulkhead inside acargo container so that an entire bottom section of the bulkhead can beremoved, to allow cargo to be discharged from the cargo containerwithout interfering with the way in which the bulkhead is supportedinside the cargo container.

A further object of this invention is to pull a liner out from a bulkcargo container by winding the liner onto a mechanism that is mountedand locked directly onto the cargo container.

Another object of the present invention is to provide a mechanism forpulling a liner from a bulk cargo container, that can be easily mountedand locked directly onto standard size intermodal cargo containers.

A still further object of this invention is to provide a mechanism topull a liner from a cargo container, and that is very simple andeconomical to manufacture, install, and operate.

These and other objectives are attained with a cargo containercomprising a container body, a floor liner, and a rear bulkhead. Thecontainer body defines an interior cargo space for holding a cargo, anda back opening for conducting cargo into and discharging cargo from thatcargo space. The liner is positioned on the container floor in asequence of overlapping pleats or with a series of spaced rolls thatallow the length of the liner to expand. The bulkhead is held inside thecontainer body, immediately forward of a back wall thereof, to hold thecargo in the cargo space. In particular, the bulkhead is suspendedinside the cargo container--that is, the bulkhead is not significantlysupported by the floor of the container, but instead is supported by thesides, the roof, or by both the sides and the roof of the container.

To unload cargo from the container, an opening is formed in the bottomof the bulkhead, and the liner is pulled out from the cargo container.As the liner is so pulled, cargo is pulled out with the liner; and atthe same time, the pleats or rolls of the liner unfold and unroll,expanding the length of the liner. The dimensions of the liner,particularly the size and number of pleats or rolls, are selected sothat the liner is able to pull out substantially all of the cargo fromthe container as the liner itself is pulled out of the cargo container.

Preferably, a mechanical apparatus is directly mounted on the cargocontainer to pull the liner out therefrom; and this pulling apparatuscomprises a frame, a mandrel, drive means, and connecting means. Themandrel is rotatably supported by and laterally extends across the frameof the pulling apparatus, and the mandrel includes means to connect thefloor liner of the cargo container to the mandrel. The drive means ofthe pulling apparatus is mounted on the frame and engages the mandrel torotate the mandrel and wind the container floor liner therearound. Theconnecting means of the pulling apparatus is mounted on the frame toconnect the pulling apparatus to the cargo container, preferablyimmediately rearward of and below the bottom edge of the back opening ofthe cargo container.

Further benefits and advantages of the invention will become apparentfrom a consideration of the following detailed description given withreference to the accompanying drawings, which specify and show preferredembodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a bulk cargo container.

FIG. 2 illustrates a cargo being loaded into the container of FIG. 1.

FIG. 3 shows the cargo being discharged from the cargo container.

FIG. 4 is a back perspective view of a pleated sheet used to line thefloor of the cargo container.

FIG. 5 is an enlarged, perspective view of a portion of the pleatedliner of FIG. 4.

FIG. 6 is a back perspective view of an alternate liner that may be usedin the cargo container of FIGS. 1-3.

FIG. 7 is an enlarged, perspective view of a portion of the liner ofFIG. 6, showing how the rolls of the liner may be formed.

FIG. 8 is a side view of a portion of the liner shown in FIG. 7.

FIG. 9 is a back view of the bulkhead used in the cargo container ofFIGS. 1-3, and shows one arrangement for suspending the bulkhead insidethe cargo container.

FIG. 10 illustrates how a support strap for the bulkhead may be mountedon the cargo container.

FIG. 11 shows an alternate arrangement for suspending the bulkheadinside the cargo container.

FIG. 12 shows a third arrangement for suspending the bulkhead inside thecargo container.

FIG. 13 illustrates how a reinforcing bar for the bulkhead may besupported inside the cargo container.

FIG. 14 is a perspective view of an apparatus for pulling a floor linerfrom the cargo container of FIGS. 1-3.

FIG. 15 is a top view of the pulling apparatus of FIG. 14.

FIG. 16 is a perspective view of a corner casting of the cargo containershown in FIGS. 1-3.

FIG. 17 is a top view of one of the connecting assemblies of theapparatus of FIGS. 14 and 15.

FIG. 18 shows the connecting assembly of FIG. 17 inserted into thecorner casting of FIG. 16.

FIG. 19 shows the connecting assembly locked inside the corner casting.

FIG. 20 shows the connecting assembly tightly clamped onto the cornercasting.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1-3 illustrate cargo container 100 generally comprising containerbody 102, liner 104, and bulkhead 106. Generally, container body 102defines an interior cargo space 110 for holding a cargo; and thecontainer body includes a floor 112, roof 114, front and back walls 116and 120, and left and right side walls 122 and 124. Back wall 120includes a pair of outwardly hinged doors 120a and 120b, and when thesedoors are open, the back wall forms an opening that provides access tothe interior of the cargo container. Liner 104 is positioned oncontainer floor 112 in a sequence of overlapping pleats or foldedsections 126 that allow the length of the liner to expand; and thebulkhead 106 is secured inside container body 102, immediately forwardof back wall 120, to hold a cargo in cargo space 110.

Generally, in operation, a bulk cargo 128 is loaded into cargo space 110and onto liner 104. Suitable inlet openings (not shown) may be providedin bulkhead 106 to allow the cargo to pass therethrough and into cargospace 110, or the cargo may be conducted into that cargo space throughthe area above the top of the bulkhead. Once the container is loadedwith cargo, it is transported, and the container is unloaded after itreaches its destination.

To unload cargo 128 from container 100, an opening 130 is formed in thebottom of bulkhead 106 and liner 104 is pulled outward from the cargocontainer. As the liner is so pulled, cargo 128 is pulled out with theliner; and at the same time, the pleats 126 of the liner unfold,expanding the length of the liner. The dimensions of liner 104,particularly the size and number of pleats 126, are selected so that theliner is able to pull out substantially all of the cargo from thecontainer as the liner itself is pulled out of the container cargo.Preferably, as discussed in detail below, a mechanical apparatus ismounted on cargo container 100 to pull liner 104 out therefrom.

Any suitable cargo container 100 may be employed in the practice of thisinvention, although preferably container body 102 has a conventionalsize and shape. Even more preferably, container body 102 is of the typereferred to in the art as intermodal and can be transported by truck,railroad, and ship.

FIGS. 4 and 5 illustrate liner 104 in greater detail. With particularreference to FIG. 4, liner 104 has a generally elongated, rectangularshape, including front and back edges 104a and 104b. Also, the foldedsections 126 of liner 104 are spaced apart along the length of theliner; and each of the folded sections of the liner extends completelyacross the width of the liner, substantially perpendicular to thelongitudinal axis of the liner. Moreover, over substantially, andpreferably over completely, the entire length of the liner, the foldsare directed toward the back edge of the liner.

More specifically, each folded section includes front and back edges;and in each pair of adjacent forward and rearward folded sections, theback edge of the forward one of that pair of sections is positioned ontop of the rearward one of that pair of sections. For example, in FIGS.4 and 5, four folded sections are specifically referenced at 126a, 126b,126c, and 126d. The front and back edges of section 126a are referencedat 126a-1 and 126a-2 respectively, and the front and back edges ofsection 126b are referenced at 126b-1 and 126b-2 respectively.Similarly, the front and back edges of section 126c are respectivelyreferenced at 126c-1 and 126c-2, and the front and back edges of section126c are respectively referenced at 126d-1 and 126d-2. The back edge122a-2 of section 122a is on top of folded section 122b, the back edge122b-2 of section 122b is on top of folded section 122c, and the backedge 122c-2 of this latter section is on top of folded section 122d.

The number and widths of the folded sections 126 of liner 104 are chosento help ensure that cargo 128 is completely unloaded from cargocontainer 100 as the liner is pulled out therefrom. However, each foldedsection may have a random width, and these folded sections may berandomly spaced along the length of liner 104. That length is anothervariable that may be selected to help ensure that cargo 128 iscompletely unloaded from cargo container 100 as the liner is pulled outtherefrom; and indeed, preferably, when the liner is installed in thecargo container, the liner extends at least over the complete length offloor 112, and also partially or completely extend over front wall 116.The front portion of liner 104 may be provided with attachment means,such as eyelets or loops to help secure the liner inside cargo container100; and the back end portion of the liner preferably has truncatedcorner portions to help pull the liner out of the cargo container, asdiscussed in greater detail below.

In addition, small heat welds, for example, as shown at 132, may be usedto connect together folded sections 126 to maintain those foldedsections held against each other inside cargo container 100 until liner104 is pulled out of the container. Each heat weld has very littleresistance and is broken as soon as an appreciable pulling force isapplied to the bottom of the two layers joined by the heat weld.Adjacent folded sections may be suitably connected together in otherways, though; and for example, adjacent sections may be stitchedtogether for this purpose.

FIGS. 6-8 illustrate an alternate liner 134 that may also be used topull a bulk cargo from cargo container 100, and that includes amultitude of rolled sections 136, rather than a multitude of overlappingpleats 126, spaced along the liner to allow the length of the liner toexpand as it is pulled outward from the cargo container. Each rolledsection 136, includes a section of liner 134 rolled about a given axis.Preferably, each rolled section 136 laterally extends completely acrossthe width of liner 134, substantially perpendicular to the longitudinalaxis thereof. The specific number of rolled sections 136 in liner 134,and the size of each rolled section may vary, however, depending on thespecific application for which a particular liner is intended.

FIGS. 7 and 8 particularly illustrate one procedure that may be used toform rolled sections 136. To form a rolled section, two adjacentportions of liner 134 are brought together, for example as shown at 140,so as to form a top edge 142; and then these two adjacent portions ofthe liner are progressively rolled together about that edge, as shown at144a, 144b, 144c, and 144d, until the desired length or amount ofmaterial has been rolled together.

Preferably, after a given section of liner 134 has been rolled together,means are applied to the formed roll to hold the material thereof inthat roll. For instance, one or more heated pins 146 may be insertedinto or through each roll to prevent the material thereof fromprematurely unravelling; and preferably, a multitude of such pins areinserted into each roll at a multitude of locations uniformly spacedalong the length of the roll. Alternatively, adhesive tape may appliedover each roll and connected to adjacent portions of liner 134, on oneor both sides of the roll, to prevent the roll from prematurelyunravelling.

Both liners 104 and 134 may be made from any suitable material, althoughpreferably the liners have a high resistance to stretching at leastalong the lengths of the liners. For example, the liners may beconstructed of woven polyethylene or woven polypropylene fabric having athickness of about seven mils. Alternatively, the liners may be madefrom strips, such as two inch strips of fiberglass tape, metalreinforced tape, or polyester reinforced tape, or the liners could bemade from co-extruded cross-laminated plastic film, or coextruded, orcross laminated film. As still additional examples, the liner may bemade from natural materials such as cotton.

As previously mentioned, and with reference again to FIGS. 1-3, bulkhead106 is secured inside cargo container 100, immediately forward of backwall 120, to hold a cargo in cargo space 110. In particular, thebulkhead is used to hold the cargo in that space both while the cargo isbeing loaded thereinto and while the container is being transported. Aswill be understood by those of ordinary skill in the art, typically, adischarge opening must be formed in the bulkhead to allow cargo to bedischarged from the cargo container. In order to achieve a completeunloading of the cargo when cargo is discharged from container 100 bymeans of a procedure in which a bottom liner is pulled out from thecontainer, it is important that a wide opening be formed across thebottom of the bulkhead.

Heretofore, however, it has been difficult to form suitable wideopenings in the bottoms of bulkheads of the general type used to holdbulk cargo in cargo containers. This is because these prior artbulkheads have been supported by the floors of the cargo containers; andany very wide opening formed in the bottom of such a bulkhead weakensthe bulkhead, and the bulkhead may partially collapse and interfere withthe flow of the product outward from the cargo container.

In accordance with one aspect of the present invention, these prior artdifficulties are overcome by suspending bulkhead 106 inside cargocontainer 100--that is, the bulkhead is supported by a portion of thecargo container other than floor 112 thereof, and for example, thebulkhead may be supported by the sides 122, 124, by the roof 114, or byboth the sides and the roof of the cargo container. In this way, anopening may be formed completely across the bottom of the bulkhead, or abottom portion of the bulkhead may be removed, to allow cargo to bedischarged from the cargo container without significantly interferingwith the way in which the bulkhead is supported inside the cargocontainer.

FIGS. 9-13 illustrate a preferred embodiment of bulkhead 106 and variousarrangement for suspending the bulkhead inside cargo container 100.FIGS. 9, 11, and 13 also show a pair of reinforcing members or bars 152that are mounted inside cargo container 100 to reinforce bulkhead 106.More specifically, reinforcing bars 152 are located rearward of bulkhead106, extend laterally across the bulkhead, and engage both the bulkheadand the cargo container body to transfer loads on the bulkhead to thecargo container body.

With the support arrangements shown in FIGS. 9-11, at least one andpreferably two straps 154, 156 are connected to upper portions of cargocontainer 100 and used, either directly or indirectly, to suspendbulkhead 106 therewithin. For example, with particular reference toFIGS. 9 and 10, a first end of each strap, for example end 156a of strap156, may be looped over a hook or bar 160 mounted on an inside surfaceof cargo container 100, and a second end of each strap may be insertedthrough one or more slits 162 formed in the bulkhead. The ends of eachstrap may be tied or connected together, forming one large loop fromstrap 154 and one large loop from strap 156 to mount the bulkhead on thecargo container. Alternatively, each end of each strap 154, 156 may betied to a respective adjacent portion of the strap, forming top andbottom smaller loops on strap 154, and top and bottom smaller loops onstrap 156 to mount the bulkhead on the cargo container. As a stillfurther alternative, each strap end may be tied to a respective portionof cargo container 100, or to a respective hook or bar mounted on theinside surface of the cargo container, to hold bulkhead 106 thereon.

As will be appreciated by those of ordinary skill in the art, numerousother procedures may be used to connect straps 154, 156 to cargocontainer 100 and to bulkhead 106, and for instance., the straps may bestapled to the bulkhead. Further, straps 154, 156 may be employed tohold reinforcing bars 152 in place; and for example, as generallydepicted in FIG. 9, each strap may be wrapped or looped around, orsimply extend over a respective one side of each of bars 154 and 156,for instance as shown at 164, to hold those bars.

FIG. 11 illustrates a technique for using straps 154, 156 to indirectlysuspend bulkhead 106. With this procedure, one of the reinforcing bars152, for example the lower of these two bars, is directly suspended bystraps 154 and 156, and then a second set of straps, referenced at 166,are mounted on or wrapped around that one reinforcing bar and used tosuspend bulkhead 106. More particularly, straps 154, 156, preferably thelower ends 154b, 156b thereof, are looped around, wrapped around, orotherwise connected to one of the reinforcing bars, preferably to sidesthereof, to hold the reinforcing bar in place. Similarly, each of straps166 is looped or wrapped around or otherwise mounted on the onereinforcing bar and connected to bulkhead 106. These straps 166 may beconnected to bulkhead 106 in any suitable way; and for example, ends ofstraps 166 may be inserted through slits 162 and tied together on thefront side of the bulkhead. Alternatively, straps 166 may be stapled orglued to the bulkhead. With this general procedure, a third set ofstraps 170 may be connected to or mounted on bulkhead 106 and looped orwrapped around the second of the reinforcing bars to hold that bar inits desired position adjacent the bulkhead.

FIGS. 12 and 13 illustrate another procedure for suspending bulkhead 106from one or both of the reinforcing bars 152. In this case, however, theends of that one or both of the reinforcing bars extend into smallrecesses or notches (one of which is shown at 172 in FIG. 13) formed inthe side walls 122, 124 of cargo container 100, and are thus directlysupported by those side walls, rather than by straps 154, 156. In theevent that only one of the reinforcing bars 152 is supported in notches172, a set of straps 174 is wrapped or looped around that reinforcingbar and connected to bulkhead 106 to suspend the bulkhead from thatreinforcing bar. A second set of straps 176 may be connected to bulkhead106 and wrapped or looped around the second reinforcing bar to hold thatbar in place. In the event that both reinforcing bars 152 extend intoreceiving notches 172 in the side walls of cargo container 100, a set ofstraps is mounted on either of those bars and connected to the bulkheadto support the bulkhead; and if desired, a second set of straps may bemounted on the other of the reinforcing bars and also connected to thebulkhead to further support the bulkhead.

Straps 154, 156, 166, 170, 174 may be made of any suitable material,although preferably they are made from a high strength material. Forinstance, the straps may be constructed of woven polyethylene andpolypropylene, or the straps may be made from strips of fiberglasstapes, metal reinforced tapes, or polyester reinforced tapes. As stilladditional examples, the support straps 154, 156, 166, 170, 174 may bemade from coextruded cross laminated plastic film, or coextruded, orcross laminated film.

Preferably, bulkhead 106 is comprised of upper and lower separablesections 106a and 106b; and in use, the lower section of the bulkhead isseparated and removed from the upper section to form a discharge openingor outlet in the bulkhead. Bulkhead sections 106a and 106b may bereleasably connected together in any suitable manner; and for example,these bulkhead sections may be stapled or nailed together.Alternatively, one of these bulkhead sections may be provided with aplurality of hooks, and the other of the bulkhead sections may beprovided with a plurality of openings or eyelets adapted to mount ontothose hooks to connect the two bulkhead sections together. As will beunderstood, it is not necessary that the bulkhead be comprised ofseparable sections; and for instance, the bulkhead may be formed fromone piece or section of material, and a lower portion or area of thebulkhead may be cut away from an upper portion thereof to form thedesired discharge opening in the bulkhead.

Preferably, bulkhead 106 is made from a corrugated cardboard material,and is provided with suitable openings or suitable score lines tofacilitate the formation of suitable openings, to allow material to beloaded into the cargo container through the bulkhead. The bulkhead maybe made of any other suitable material, though; and, for instance, thebulkhead may be made from wood. Moreover, reinforcing bars 152 arepreferably made from a metal, although these bars may be made from othermaterials such as wood.

FIGS. 14 and 15 illustrate an apparatus 200 for pulling liner 104outward from cargo container 100; and, generally, this apparatuscomprises frame 202, mandrel 204, drive means 206, and connecting means210. Connecting means 210 is mounted on frame 202 to connect unloadingapparatus 200 to cargo container 100, preferably immediately rearward ofand below the bottom edge of the back opening thereof. Mandrel 204 isrotatably supported by and laterally extends across frame 202 andincludes means 212 to connect liner 104 to the mandrel, and drive means206 is mounted on the frame and engages the mandrel to rotate themandrel to wind the liner therearound and, thereby, to pull the lineroutward from cargo container 100.

More specifically, frame 202 includes main transverse beam 214, left andright side beams 216 and 220, and left and right stabilizing members 222and 224. Transverse beam 214 is adapted to extend laterally across cargocontainer 100, immediately adjacent or slightly below the bottom edge ofthe back opening thereof. Left and right side beams 216 and 220 areconnected to and extend rearward from the left and right sides,respectively, of beam 214, and mandrel 204 is rotatably supported by andlaterally extends between the left and right side members.

In use, as liner 104 is wound around mandrel 204, apparatus 200 may tendto pivot upward about main transverse beam 214, and stabilizing members222 and 224 are provided to limit or to prevent such pivoting movement.In particular, left and right stabilizing brackets 222 and 224 areconnected to and extend upward from the left and right sides of beam214, respectively; and in case apparatus 200 tends to pivot upward abouttransverse beam 214, those stabilizing brackets engage or abut againstthe left and right back sides of cargo container 100, preventing furthersuch pivoting movement and thereby stabilizing frame 202 and the entireunloading apparatus 200 during the unloading process.

The various members or elements of frame 202 may be made of any suitablematerial and can be connected together in any suitable way. Forinstance, these elements may be made from a metal and welded or boltedtogether.

Mandrel 204 is rotatably mounted on frame 202; and more specifically,the mandrel is rotatably supported by and laterally extends between sidebeams 216 and 220 of the frame. To pull a liner 104 from cargo container100, the back end of that liner is connected to mandrel 204, and thenthe mandrel is rotated to wind the liner onto and around the mandrel204. To facilitate connecting liner 104 to the mandrel, the mandrelpreferably includes an axially extending slot 212 that radially extendscompletely through the mandrel; and with particular reference to FIGS. 4and 14, to connect liner 104 to mandrel 204, the back edge 104b of theliner is pulled through slot 212, and then the mandrel is rotated towind the liner onto the mandrel.

Drive means 206 is mounted on frame 202 and is provided to rotatemandrel 204, and preferably the drive means includes a winch 226 and amotor or engine 230. Winch 226 is mounted on frame 202, specificallyleft side member 216, and is directly connected to mandrel 204 to rotatethe mandrel. Engine or motor 230 is also mounted on frame 202 and isconnected to winch 216 to operate that winch. Any suitable winch, motor,or engine may be used in the practice of the present invention.

However, often cargo containers of the general type disclosed in FIGS.1-3 are transported by trucks or other vehicles that includes a powersource, such as a hydraulic pump, an electric battery or an electricgenerator; and preferably, motor 230 is one that can be operated by thepower source on the vehicle that carries the cargo container 100. Inparticular, if this vehicle has a hydraulic pump, it may be preferred toprovide unloading apparatus 200 with a hydraulic motor; while if thetransporting vehicle has an electric battery or generator, it may beappropriate to provide apparatus 200 with an electric motor.

Connecting means 210 preferably includes left and right connectingassemblies 232 and 234 mounted, respectively, on the left and rightsides of frame 202 to connect the frame, respectively, to left and rightsides of cargo container 100. An important advantage of apparatus 200 isthat the connecting assemblies 232 and 234 thereof are particularly welladapted to mount apparatus 200 onto an intermodal cargo container havingconventional, lower back corner castings spaced apart a standarddistance.

To elaborate, standard intermodal cargo containers of the type shown inFIGS. 1-3 typically have corner members, referred to as corner castings,located at, among other places, the back lower left and back lower rightcorners of the container body. One corner casting is shown at 236 inFIG. 18; and as illustrated therein, the corner castings form amultitude of openings 240 that are used to lock the cargo containersonto supporting members such as trucks or railroad car frames or othercontainers. Because of the way in which these corner castings are used,industry standards have developed that govern the size, shape, andspacing of the corner castings. In order to make apparatus 200 very easyto mount onto a cargo container having such lower back corner castings,connecting assemblies 232 and 234, first, are specifically designed tolock into corner castings, and second, are spaced apart a distancesubstantially equal to a standard distance between such corner castings.

Left and right connecting assemblies 232 and 234 are substantiallyidentical, and thus only one will be described herein in detail. Withreference to FIG. 17, each of the connecting assemblies includes twistlock 242, handle 244, spacer 246, support rod 250, and adjusting nut252. Twist lock 242 is rotatably mounted on frame 202, specificallytransverse beam 214, adjacent one end thereof; and handle 244 isconnected to the twist lock to pivot that lock to facilitate insertingthe twist lock into, and then locking it inside, one of the cornercastings of cargo container 100. More specifically, twist lock 242 ispivotal between, and handle 244 is used to pivot the twist lock between,first and second positions shown in FIGS. 18 and 19, respectively. Inthis first position, twist lock 242 can be inserted through an opening240 in, and into the interior of, corner casting 236; and in the secondposition, twist lock 242 is locked inside corner casting 236.Preferably, as illustrated in the drawings, twist lock 242 is disposedon a forward or front side of beam 214, and handle 244 is disposed on arearward or back side of that beam.

Twist lock 242 may be pivotally mounted on beam 214 and handle 244 maybe connected to the twist lock in any suitable way. For example, athrough opening 254 may be formed in beam 214, and rod 250 may beinserted through that opening such that the rod is supported by beam 214and is rotatable in opening 254. At the same time, twist lock 242 isrigidly mounted on a forward end of rod 250, and handle 244 is connectedto a back end of rod 250.

Spacing member 246 is connected to transverse beam 214, between thatbeam and twist lock 242, to maintain the twist lock spaced from thetransverse beam. This facilitates inserting the twist lock into theinterior of corner casting 236 and locking the twist lock therein. Asshown in FIG. 17, preferably, support rod 250 also extends throughspacing member 246.

Preferably, each connecting assembly 232 and 234 also includestightening means connected to the twist lock to pull the twist locktoward transverse beam 214 and thereby to connect frame 202 tightly to arespective one of the corner casting members on container 100. With theembodiment of connecting assembly 232 illustrated in the drawings, thistightening means comprises adjusting nut 252, which is threadablymounted on rod 250, rearward of beam 214. In operation, once twist lock242 is locked inside corner casting 236, nut 252 is threaded forward onrod 250 to bring the nut into engagement with the backside of beam 214and then to Dull rod 250 and twist lock 242 rearward, thereby clampingthe corner casting securely between twist lock 242 and beam 214, asshown in FIG. 20.

While it is apparent that the invention herein disclosed is wellcalculated to fulfill the objects previously stated, it will beappreciated that numerous modifications and embodiments may be devisedby those skilled in the art, and it is intended that the appended claimscover all such modifications and embodiments as fall within the truespirit and scope of the present invention.

We claim:
 1. A method of unloading a bulk cargo from a cargo containerof a type defining a cargo space for holding a bulk cargo, saidcontainer having a floor, a ceiling above and facing the floor, facingside walls on opposite sides of the floor between the floor and ceiling,a front wall at a front end of the container, and a back opening at arear end of the container defined by a back edge of the walls, the floorand ceiling, for loading cargo into and discharging cargo from the cargospace, the method comprising the steps of:suspending a bulkhead in theback opening from an upper portion of the container by positioning atleast one bar laterally between the side walls and attaching the atleast one bar to the bulkhead and attaching a first end of at least onestrap to the at least one bar, and a second end of the at least onestrap to an upper portion of the container, so that the bulkhead issuspended above the floor and does not depend on the floor for support;positioning a liner on the floor over substantially the entire floorfrom the rear opening to at least the front wall; loading a bulk cargointo the cargo space on top of the liner; mounting a detachablyconnected unloading apparatus directly onto the cargo container,adjacent the back opening; removing a bottom portion of the bulkhead tocreate a gap between the bulkhead and floor; connecting the liner to theunloading apparatus; and while the unloading apparatus is directlymounted on the cargo container, operating the unloading apparatus topull the liner and the bulk cargo outward from the cargo container,through the back opening thereof and the gap; the method operates suchthat as the unloading apparatus pulls the liner out of the container,the bulk cargo on top of it moves out with the liner through the gapsuch that the cargo is completely unloaded when the liner is completelypulled out of the container.
 2. A method according to claim 1, for usewith the cargo container that is of a that is connected to a vehiclehaving a power supply, and wherein the operating step includes the stepsof:connecting the unloading apparatus to the power supply; and usingsaid power supply to operate the unloading apparatus.
 3. A methodaccording to claim 2, wherein the power supply is an electric powersource.
 4. A method according to claim 2, wherein the power supply is ahydraulic power source.
 5. A method according to claim 1, wherein theunloading apparatus includes a rotatable mandrel having an axially andradially extending slot; and wherein:the connecting step includes thestep of inserting the liner into said slot; and the operating stepincludes the step of rotating the mandrel to wind the liner therearound.6. A method of unloading a bulk cargo from a cargo container of a typedefining a cargo space for holding a bulk cargo, said container having afloor, a ceiling above and facing the floor, facing side walls onopposite sides of the floor between the floor and ceiling, a front wallat a front end of the container, and a back opening at a rear end of thecontainer defined by a back edge of the walls, the floor and ceiling,for loading cargo into and discharging cargo from the cargo space, themethod comprising the steps of:suspending a bulkhead in the back openingfrom an upper portion of the container so that it does not depend on thefloor for support; positioning a liner on the floor over substantiallythe entire floor from the rear opening to at least the front wall;loading a bulk cargo into the cargo space on top of the liner; mountinga detachably connected unloading apparatus directly onto the cargocontainer, adjacent the back opening; removing a bottom portion of thebulkhead to create a gap between the bulkhead and floor; connecting theliner to the unloading apparatus; and while the unloading apparatus isdirectly mounted on the cargo container, operating the unloadingapparatus to pull the liner and the bulk cargo outward from the cargocontainer, through the back opening thereof and the gap; the methodoperates such that as the unloading apparatus pulls the liner out of thecontainer, the bulk cargo on top of it moves out with the liner throughthe gap such that the cargo is completely unloaded when the liner iscompletely pulled out of the container wherein the cargo containerincludes left and right lower corner members adjacent the back openingof the cargo container, each of the corner members forming at least oneopening, and the unloading apparatus includes left and right twistlocks, with both twist locks rotatably mounted on the unloadingapparatus with the right twist lock mechanism positioned for insertionin the at least one opening of the right corner member and the lefttwist lock mechanism positioned for insertion in the at least oneopening of the left corner member, and wherein the mounting stepincludes the steps of:inserting the left and right twist locks into theopenings of the left and right lower corner members, respectively, whilethe left and right twist locks are in a first position; locking the lefttwist lock inside the left corner member by moving the left twist lockto a second position; and locking the right twist lock inside the rightcorner member by moving the right twist lock to a second position.
 7. Amethod according to claim 6, wherein the mounting step further includesthe steps of:tightly clamping the unloading apparatus to the left cornermember after locking the left twist lock therein; and tightly clampingthe unloading apparatus to the right corner member after locking theright twist lock therein.
 8. A method according to claim 1 including thefurther steps of detachably connecting to the front wall an end of theliner which is adjacent the front wall on placing the liner in thecontainer.